This invention relates to aquarium devices, and more particularly to airstones for connection to an air hose and placement in an aquarium tank.
In most aquariums, a filter system is utilized to purify the water in the aquarium and at the same time to aerate the water. Generally, an airstone is used either by itself or in conjunction with a complete filtering system in order to achieve these goals. The airstone is connected to an air hose and is positioned adjacent the bottom or lower portion of the aquarium tank above the sand or gravel therein. Air is pumped in a conventional manner through the air hose and passes through the airstone which provides a dispersed area of air bubbles which enter into the water to provide the necessary air for the fish.
Airstones can be utilized by themselves in order to provide the necessary aeration. Additionally, they are frequently incorporated into a complete filtering system whereby, as the air passes from the airstone into the aquarium, the water from the aquarium passes through the filter to remove contaminants from the water where only the filtered water is aerated and returned to active use in the tank.
One of the problems in utilizing an airstone concerns maintaining its position adjacent the bottom or lower portion of the aquarium tank. Generally, the airstone itself is of sand material bonded together by a suitable adhesive. As the air passes therethrough, it tends to cause the airstone to become buoyant, so that frequently the airstone will float upwardly from its position in the tank. When the airstone is utilized in a complete filtering system, the weight of the filter will compensate for the tendency of the airstone to float upwardly and the filter will ensure the retention of the airstone adjacent the lower portion of the tank. However, when the airstone is utilized independently of a filtering system, it is frequently necessary to utilize compensatory devices to ensure the positioning of the airstone at the bottom of the tank. For example, frequently additional weighted material will be added to the airstone to provide sufficient weight to keep the airstone at the bottom of the tank. At other times the size of the airstone is increased purposely to provide sufficient material to give it the weight needed to keep it at the bottom of the tank. However, by adding additional weight, such as by increasing the length of the airstone, there results a tendency of the airstone itself to break due to the brittle characteristic of the airstone.
An additional problem with existing airstones is that as the air from the hose enters into the airstone, contaminants may be carried along with the flow of air and thus may clog the passage of the air at its entrance into the airstone. As a result, little air will pass through the airstone and insufficient aeration will be achieved for the aquarium tank.
Another problem concerns the sufficiency of the area providing aeration. In order to provide a proper mixture of the air throughout the aquarium tank, a large surface producing the air bubbles is desirous. However, with a conventional cylindrical airstone, only a limited amount of surface is provided, whereby a rather small wall of air bubbles is sent into the aquarium tank. For large aquarium tanks, this wall of air bubbles is insufficient to provide the needed aeration of the tank.
Additional problems with existing airstones concern the coupling arrangement between the air hose and the airstone. With existing airstones, a nozzle extending from the airstone is connected to the air hose. Existing airstones are generally cylindrical in shape and are maintained in an upright vertical position when connected to the air hose. This vertical position does not provide a large lateral dispersion of the air bubbles into the aquarium tank, and this reduces the distribution of the air bubbles within the aquarium tank.
A further problem concerns the appropriate packaging and storage of the airstones during shipment and display thereof. The airstones are frequently packaged individually. Because the airstone material is brittle and easily breakable, the packaging must provide necessary reenforcement to avoid breakage and crushing of the airstone, which increases the costs of packaging and shipment thereof.